Genetics and alcohol consumption

For years, physicians have assumed that alcohol abuse leads to cardiovascular diseases. However, other data has also appeared recently, in which moderate doses of alcohol resist initiation of these diseases, particularly coronary heart disease. On the one hand, ethanol increases arterial pressure, concentrating fatty acids and urea in the blood. On the other hand, ethanol decreases cholesterol and encourages blood protein coagulation and thrombi formation.

The action of alcohol ingested largely depends on its concentration in the blood. About 90 percent of ethanol is decomposed in the liver, with several enzymes participating in the process: alcohol dehydrogenases, acetaldehyde dehydrogenases, 2'1-class '450 cytochromes and some others. Diversity in the sequences of these enzymes’ genes, or their genetic polymorphism impacts the ethanol disintegration rate and the diseases connected with its abuse, as well as predisposition to cardiovascular diseases. For example, certain mutations in the alcohol dehydrogenase genes with Japanese men allow to oxidize ethanol 100 to 200 times quicker. Therefore, polymorphism of the genes participating in ethanol disintegration should tell upon the cardiovascular system state.

The Tomsk geneticists examined a group of patients with a diagnosis of ischemic cardiac disease and coronary atherosclerosis. The reference group consisted of practically healthy inhabitants of Tomsk. All participants to the experiment were examined from the point of view of cardiovascular system state and polymorphism of several genes: two genes of alcohol dehydrogenase (ADH1B and ADH7) and 'YP2'1 cytochrome gene.

The researchers found mutant variants of these genes, which influence blood pressure, fatty acids and lipoproteins concentration. The same genes determine the ethanol disintegration rate. The researchers assume that the genes’ influence on lipidic exchange and blood pressure is unconnected with the ethanol disintegration function. It is probable that the enzymes, whose operation is determined by these genes, perform several functions. However, these genes can probably be used as markers of alcoholic dependence.